Updated: 11/6/2018

Neisseria gonorrhoeae

0%
Topic
Review Topic
0
0
N/A
N/A
Questions
0 3
0
0
100%
0%
Evidence
0 2
0
0
Snapshot

discharge of gonorrhea
  • A 19-year-old male college student presents to the clinic complaining of a burning sensation with urination as well as purulent urethral discharge. He admits to rarely using condoms during sexual intercourse, and does not recall the last time he was tested for sexually-transmitted infections. Urinalysis is positive for leukocyte esterase and a Gram stain shows intracellular diplococci within polymorphonuclear neutrophils.
Introduction
  • Classification
    • Neisseria
      • Gram-negative diplococci
      • often intracellular within neutrophils
  • Epidemiology
    • incidence
      • the second most common bacterial sexually-transmitted infection (after Chlamydia)
    • location
      • genital tract
    • risk factors
      • unprotected sexual intercourse 
  • Pathogenesis
    • mechanism
      • molecular biology
        • pili facilitate attachment to mucosal surfaces
        • antigenic variation  
        • IgA protease allows invasion of mucosal surfaces
        • contains lipooligosaccharides (LOS) with strong endotoxin activity
      • invasion of mucosal surfaces results in inflammation
    • transmission
      • sexual
      • perinatal
  • Associated conditions
    • septic arthritis 
    • neonatal conjunctivitis (2-5 days after birth) 
      • prophylaxis with erythromycin eye drops
    • pelvic inflammatory disease (PID)
    • Fitz-Hugh-Curtis syndrome
Presentation
  • Symptoms
    • dysuria
    • purulent discharge
    • fever
    • prostatitis (men)
    • endocervicitis (women)
    • urethritis
Studies
  • Labs
    • Cervical and urethral culture
      • Thayer-Martin agar
        • selects for growth of Neisseria
        • contains vancomycin, trimethoprim, colistin, and nystatin to inhibit growth of Gram-positive organisms, Gram-negative organisms except for Neisseria, and fungi
    • Nucleic acid amplification testing (NAAT)
  • Histology
    • Gram stain of a cervical swab
      • Gram-negative kidney-shaped diplococci 
Differential
  • Chlamydia
    • distinguishing factor
      • visualization of intracytoplasmic inclusions (reticulate bodies) on histology
  • Urinary tract infection
    • distinguishing factor
      • lack of growth on Thayer-Martin agar
  • Genital herpes simplex
    • distinguishing factor
      • painful vesicles and ulcers
Treatment
  • Medical
    • IM ceftriaxone
      • add azithromycin or doxycycline for possible concomitant chlamydial infection
Complications
  • Pelvic inflammatory disease (PID)
    • may include salpingitis, endometritis, hydrosalpinx, tubo-ovarian abscess
    • risk factor for ectopic pregnancy, infertility, chronic pelvic pain, and adhesions
  • Fitz-Hugh-Curtis Syndrome
    • perihepatitis
      • infection and inflammation of liver capsule
      • adhesions of peritoneum to liver
Comparison with N. meningitidis
 
Characteristics N. gonorrhoeae N. meningitidis
Appearance
  • Kidney-bean shaped diplococci
Oxidase test
  • Positive
Polysaccharide capsule
  • No
  • Yes
Fermentation
  • Glucose ("Gonococci")
  • Maltose and Glucose ("MeninGococci")
Transmission
  • Sex
  • Respiratory
Vaccine
  • No (due to rapid antigenic variation)
  • Yes
β-lactamase production
  • Common
  • Rare
IgA protease production
  • Yes
 

Please rate topic.

Average 4.7 of 10 Ratings

Questions (3)
Question locked
Sorry, this question is for
PEAK Premium Subscribers only
Upgrade to PEAK
Question locked
Sorry, this question is for
PEAK Premium Subscribers only
Upgrade to PEAK

(M1.MC.15.74) A 26-year-old male presents to his primary care physician with complaints of burning with urination, penile discharge, and intermittent fevers. A urethral smear shows gram negative diplococci within white blood cells. The organism grows well when cultured on Thayer-Martin agar. The patient is prescribed a course of ceftriaxone and the infection resolves without further complication. One year later, the patient returns with the same infection. Which of the following best explains this lack of lasting immunity? Tested Concept

QID: 106692
1

Exotoxin release

2%

(1/60)

2

Antigenic variation

82%

(49/60)

3

Polysaccharide capsule

8%

(5/60)

4

Bruton's agammaglobulinemia

2%

(1/60)

5

Lack of necessary vaccination

2%

(1/60)

L 1 D

Select Answer to see Preferred Response

Evidences (2)
Topic COMMENTS (14)
Private Note